地球化学
地毬化學
지구화학
GEOCHIMICA
2009年
6期
600-606
,共7页
彭艳%李心清%程建中%周志红%王兵%黄代宽%程红光
彭豔%李心清%程建中%週誌紅%王兵%黃代寬%程紅光
팽염%리심청%정건중%주지홍%왕병%황대관%정홍광
演替阶段%微生物生物量%反硝化酶活性%N循环
縯替階段%微生物生物量%反硝化酶活性%N循環
연체계단%미생물생물량%반초화매활성%N순배
succession stage%soil microbial biomass%denitrification enzyme activity%nitrogen cycle
土壤营养元素赋存状态和微生物活性是喀斯特地区生态恢复的关键质量指标,温室气体N_2O的排放是全球变暖的重要因子.研究了雨季贵阳不同演替阶段森林表层土壤(0~10 cm)微生物生物量(SMB)、反硝化酶活性(DEA)、无机氮(N)库和N转化特征,并与玉米地、茂兰喀斯特原始森林土壤做了对比分析.结果表明,微生物群落对土壤水分条件响应强烈,土壤有效N的增加有助于微生物群落的增长,土壤N转化速率越快,微生物N同化作用越低.人为干扰(火烧和农业活动)会增加或降低土壤SMB、增加潜在的气态N流失.总的来说,不同演替阶段土壤SMB、DEA和土壤N库均有显著差异,随植被恢复土壤SMB呈上升趋势,温室气体N_2O的排放量呈下降趋势,气态N流失形态从N_2O转变为N_2,N循环过程趋于优化,表明自发演替是退化喀斯特森林恢复的可靠方式.
土壤營養元素賦存狀態和微生物活性是喀斯特地區生態恢複的關鍵質量指標,溫室氣體N_2O的排放是全毬變暖的重要因子.研究瞭雨季貴暘不同縯替階段森林錶層土壤(0~10 cm)微生物生物量(SMB)、反硝化酶活性(DEA)、無機氮(N)庫和N轉化特徵,併與玉米地、茂蘭喀斯特原始森林土壤做瞭對比分析.結果錶明,微生物群落對土壤水分條件響應彊烈,土壤有效N的增加有助于微生物群落的增長,土壤N轉化速率越快,微生物N同化作用越低.人為榦擾(火燒和農業活動)會增加或降低土壤SMB、增加潛在的氣態N流失.總的來說,不同縯替階段土壤SMB、DEA和土壤N庫均有顯著差異,隨植被恢複土壤SMB呈上升趨勢,溫室氣體N_2O的排放量呈下降趨勢,氣態N流失形態從N_2O轉變為N_2,N循環過程趨于優化,錶明自髮縯替是退化喀斯特森林恢複的可靠方式.
토양영양원소부존상태화미생물활성시객사특지구생태회복적관건질량지표,온실기체N_2O적배방시전구변난적중요인자.연구료우계귀양불동연체계단삼림표층토양(0~10 cm)미생물생물량(SMB)、반초화매활성(DEA)、무궤담(N)고화N전화특정,병여옥미지、무란객사특원시삼림토양주료대비분석.결과표명,미생물군락대토양수분조건향응강렬,토양유효N적증가유조우미생물군락적증장,토양N전화속솔월쾌,미생물N동화작용월저.인위간우(화소화농업활동)회증가혹강저토양SMB、증가잠재적기태N류실.총적래설,불동연체계단토양SMB、DEA화토양N고균유현저차이,수식피회복토양SMB정상승추세,온실기체N_2O적배방량정하강추세,기태N류실형태종N_2O전변위N_2,N순배과정추우우화,표명자발연체시퇴화객사특삼림회복적가고방식.
Soil nutrients distribution and microbial activity are key qualitative index of ecology recovery in Karst regions. The emission of greenhouse gas N_2O is an important factor in global warming. We have studied soil microbial biomass (SMB), denitrification enzyme activity (DEA) and nitrogen cycling characteristics on surface soil (0 ~ 10 cm) at different succession stages of forest, and compared with corn field and Maolan original forest. The results show that microbial community responses strongly to soil moisture conditions. Increasing soil available nitrogen is beneficial to the increase of microbial communities. Microbial nitrogen assimilation becomes lower when soil N converted faster. Human disturbance (fire, agricultural activities) increases or decreases the microbial biomass and increase the potential gaseous N emission. In general, microbial biomass, denitrification enzyme activity and soil N pool are significantly different during succession. Microbial biomass tends to increase but greenhouse gas N_2O emission tends to reduce during the recovery of forest vegetation. The forms of gas N emission changes from N_2O to N_2 which optimizes the nitrogen cycle. Therefore, self-succession is a reliable method of degraded Karst forest restoration.